Question

Question

Which of the following equations shows a chemical change?(1 point)
Responses

C2H5OH(l)→C2H5OH(g)
C 2 H 5 O H, which is a liquid right-arrow C 2 H 5 O H, which is a gas

NH3(g)→NH3(l)
N H 3, which is a gas right-arrow N H 3, which is a liquid

H2O(s)→H2O(g)
H 2 O, which is a solid right-arrow H 2 O, which is a gas

C3H8+5O2→3CO2+4H2O

Answer 1

The equation that shows a chemical change is:

C3H8 + 5O2 → 3CO2 + 4H2O

This reaction represents the combustion of propane (C3H8), where it reacts with oxygen (O2) to produce carbon dioxide (CO2) and water (H2O). In this process, new substances are formed, indicating a chemical change.

The other equations represent physical changes, specifically phase changes (liquid to gas, gas to liquid, solid to gas), where the chemical identity of the substances remains the same.